Field of the Invention
The present invention relates to an electronics unit having a resin-sealed structure in which a circuit board with an electronic component mounted thereon includes a card-edge terminal for electrically connecting the circuit board detachably to an equipment external to the circuit board, and particularly relates to an improvement of the attachment mechanism between a connector housing connected to an external wiring and the main body of the electronics unit.
Description of the Related Art
An electronic control unit in which a circuit board with an electronic component mounted thereon includes at its edge a card-edge terminal for external connection which are integrally molded with a sealing resin is well known. For example, according to FIGS. 2 and 3 of PTL 1 listed below, “CARD MEMBER AND CARD-EDGE CONNECTOR,” a board 12 having a card-edge part 14 with a plurality of card-edge terminals 13 to be connected to a counterpart connector 31 formed at least on one side of the card-edge part 14, and a card member 11 including a cover body 15 covering the board 12 are provided, in which the cover body 15 includes an opening 26 through which at least the card-edge terminals 13 are exposed and a container 18 filled with filling material and containing the board 12.
Also, in a card-edge connector 10, the card member 11 is connected to the counterpart connector 31, which protects the card-edge terminals from an impact of falling or the like and provides the card member and card-edge connector having superior waterproofing capability. Note that, according to FIG. 12, a card member 11A can be molded using molds 43, 44. Note that the above reference numerals are ones used in PTL 1.
According to FIG. 3 of PTL 2 listed below, “ELECTRIC/ELECTRONIC CONTROL UNIT AND METHOD FOR MANUFACTURING THE SAME,” electronic components 1a, 1b mounted on a circuit board 2 are resin-sealed by a transfer mold molding method using a thermosetting resin 5, then an external connection terminal 3 is solder-mounted on the circuit board 2 and integrally molded by an injection molding method using a thermoplastic resin 7 to configure a connector 60 from part of the thermoplastic resin 7, which can suppress decrease in productivity due to increase in size of an electronic circuit board and can eliminate the need for previously forming a connector housing 4 using a thermosetting resin shown in FIG. 1. Note that the above reference numerals are ones used in PTL 2.
[PTL 1] JP-A-2013-182299 (FIG. 2, FIG. 3, Abstract, Paragraph 0001, FIG. 12, Paragraph 0066)
[PTL 2] JP-A-2010-067773 (FIG. 1, Abstract, FIG. 3, Paragraph 0048, Paragraph 0051)
(1) Description of Problem of Prior Art
According to the PTL 1, the cover body 15 of the card member 11 is connected to a housing 32 of the counterpart connector 31 such that a plurality of engaging projections 19 are fitted into a plurality of engaging grooves 35 and the cover body 15 and the housing 32 are fixed to each other by a locking part 20 and a locking mechanism 36.
However, when the card member 11 with the counterpart connector 31 not connected thereto is transported and delivered to a site at which assembly should be performed, the card-edge part 14 is exposed, so, the card-edge terminals 13 cannot be protected. Also, when the card member 11 is connected at the site, the engaging projections 19 and the engaging grooves 35, and the locking part 20 and the locking mechanism 36 may be damaged.
This problem tends to occur when the cover body 15 is made of a thermosetting sealing resin and integrally molded with the board 12. In order to improve the strength of the sealing resin, with high hardness and prone to crack failure, the thickness of the high-cost thermosetting sealing resin needs to be increased. Note that the above reference numerals are ones used in PTL 1.
According to the PTL 2, the connector 60 is protected by the thermoplastic resin 7 and the thermoplastic resin 7 is not damaged by the insertion and withdrawal of the counterpart connector not shown. However, two stages of component mounting process (for the electronic components 1a, 1b and external connection terminal 3), two stages of soldering process (for the electronic components 1a, 1b and external connection terminal 3) and two stages of assembling and molding process (for transfer molding using the thermosetting resin 5 and injection molding using the thermoplastic resin 7) are needed, which poses a problem of requiring large scale equipment and increasing the product price. Note that the above reference numerals are ones used in PTL 2.